Counter voltage track circuits



All@ 18, 1954 F. H. wlNKs ETAL 3,145,002

COUNTER VOLTAGE TRACK CIRCUITS Filed Oct. 17, 1962 2 Sheets-Sheet 1{Voqrgg/o/Rcs r1-i l o- /4 2 REL/w gg n!!q M /3/ f6 f /5/ 20 /7 Tic. E.

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INVENTORS /C/eg /f h//A/Ks ug- 18, 1964 F. H. wlNKs ETAL 3,145,002

COUNTER VOLTAGE TRACK CIRCUITS Filed Oct. 17, 1962 2 Sheets-Sheet 2/PELA/ 4/ f5 F 7. 50 .if

IN VENTORS United States Patent O 3,145,002 CDUNTER VOLTAGE TRACKCIRCUITS Fred H. Winks, 434 78th St., Brooklyn, N.Y., and Henry G.Wanser, 538 E. 142nd St., New York, N.Y. Filed Oct. 17, 1962, Ser. No.231,170 1 Claim. (Cl. 246-33) Our invention relates to track circuitsand more speciiically to a counter-voltage track circuit for positivelycontrolling the signalling means.

In track circuit signalling systems in use at present, when the tracksection is occupied by a train, the trains wheels shunt the current awayfrom the track relay, deenergizing the relay and causing the relay vaneto drop to the downward position by gravity. When the train has left thetrack section, the relay becomes energized and functions to lift thevane. Operation of the vane of the track relay by gravity isunsatisfactory as friction, vibration, and stray electric currents canat times prevent gravity from operating the vane to the downwardposition. This causes the relay to function improperly and produces anincorrect signal. In addition, after the vane has dropped, gravity maynot be suiiicient to hold it down against the action `of stray currentsand vibration. This undesirable movement of the vane, and the relaycontacts, tends to cause arcing across, and pitting of, these relaycontacts.

Therefore it is an object of the present invention to augment thegravitational force, which now drops the vane, by adding anelectro-magnetic force'to positively operate the vane to the downwardposition, when the track section is occupied.

A further object of the invention is to secure the vane in its downwardposition against the action of stray currents and vibration, thuspreventing arcing across the relay contacts and consequent pitting ofthese contacts.

Another object is to add an electro-magnetic force to the gravity forceacting on the vane to speed up the operation of the vane in its downwardtravel.

We accomplish these and other objects by inserting in the track circuita secondary voltage source which is smaller than, and of oppositepolarity to, the primary source, and positioned at the same end of thetrack circuit as the relay.

For further comprehension of the invention and of the objects andadvantages thereof, reference will be had to the following description,the accompanying drawing and to the appended claims in which the variousnovel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure:

In the drawings, FIG. 1 is a combined wiring and schematic drawing of atrack circuit embodying our invention.

FIG. 2 is a side view of a relay of the track circuit, together with itscontacts, and with its vane in the upward position.

FIG. 3 is a view similar to that shown in FIG. 2 but with the vane inthe downward position and with the contacts reversed.

FIG. 4 is a top View of the relay shown in FIGS. 2 and 3.

FIG. 5 is a modiiication of the invention shown in FIG. 1, showing analternating current track circuit which may be used where direct currentis used for train propulsion.

FIG. 6 is a further modification of the invention shown in FIG. 1,showing another type of alternating current track circuit which may beused where direct current is used for train propulsion.

FIG. 7 is another modification of the invention shown in FIG. l showinga direct current track circuit.

In the drawing and in the specication, in which like 3,145,002 PatentedAug. 18, 1964 icc numerals indicate similar elements (see FIG. 1),numeral 10 indicates an alternating current track circuit embodying theinvention and comprised of a signal rail 11, return rail 12, a feed andequipment group 13, a relay end equipment group 14, and a conventionaltwo element track relay 15.

The feed and equipment group 13 is comprised of a track transformer 16,resistor 17, and fuse 18, which are connected in a series arrangement tothe rails at the feed end of the track circuit.

The relay end equipment group 14 is comprised of a transformer 19, aresistor 20, and a fuse 21, which are connected in a series arrangementwith the relay 15, to the rails at the relay end of the track circuit.It should be noted here that the voltage of the track transformer 16 islarger than the voltage of the transformer 19 and is of oppositepolarity to it.

The conventional two element relay 15 is comprised of a frame 22 (partlyshown) supporting a local electromagnet core 23, whose coils areconnected to the constant potential voltage source, a trackelectro-magnet core 24 whose coils are directly connected to a rail andthe relay end equipment group 14, a rotatable vane 25, an upper contact26, and a lower contact 27. The vane 25 is operated by the interactionof the two electro-magnet cores. When the vane is in an upward positionupper contact 26 is closed and lower contact 27 is open; when the vaneis in a downward position contact 26 is open and contact 27 is closed;thus a direct signal is produced, or an electric control is provided,whereby a signal can be given.

Now, referring back to the relative voltage settings of transformers 16and 19-the purpose of these relative voltage settings is to permit therequired amount of control current to pass through the circuit andyfunction on the coils of the track electro-magnet 24 to raise the vane25 and hold the vane raised (see FIG. 2), and so produce a signal whenthe track section (rails 11 and 12) is unoccupied. When the tracksection is occupied a shunt occurs on the rails and the control currentfrom transformer 16 is shunted away from the relay thus preventing thecontrol current from acting on the coils of the track electro-magnet 24.However the reverse control current from transformer 19 will now passthrough the coils of the track electro-magnet 24 and being as thepolarity of this current is opposite to that of the current produced bytransformer 16, it functions on the coils of the track electro-magnet 24to cause it to operate in the opposite direcion to what would have beencaused by the current from transformer 16, and to drive the vane 25downward and hold it in a downward position (see FIG. 3), and thusproduce a different signal.

It should be noted that the present invention requires two transformersin each track section. The number of transformers required can bereduced materially if the transformers used are of such a character thatthey are provided with at least two separate secondary windings. Withthis type equipment a transformer can function in one track circuit withone of its secondary windings as the track transformer 16 and with itsother secondary winding as the transformer 19 inthe adjacent trackcircuit.

Of course the two secondary windings referred to above must producevoltages of the proper magnitde and be installed to provide the properpolarity in the track circuit.

A modification of vtrack circuit 10 is shown in FIG. 5. Here a reactor30 is positioned across the relay 15 and resistor 20. The purpose of thereactor is to shunt the direct current of the train motors away from therelay 15.

Another modification of track circuit 10 is shown in FIG. 6. Thismodification shows the feed and relay end equipment groups similar tothose shown in FIG. 1. Here the relay is different and a balancingimpedence is added in order to nullify the effects of the direct currenton the relay. This is accomplished by providing a relay 41, whose trackwinding is center tapped, in place of relay 15, and by adding abalancing impedence 42. The center tapped lead 43 of relay 41 isconnected torrelay end equipment group 14, one outside lead 44 of therelay is connected to the free end of the inductor portion 45 of thebalancing impedence, and the other outside lead 46 of the relay isconnected to the free end of the resistor portion 47 of lthe balancingimpedence. c The joined ends 48 of the resistor and inductor go to arail.

By this construction the alternating current travels through theresistor 47 and causes the relay 41 to function while the direct currentdivides between the resistor 47 and inductor 45 and has no eifect on therelay.

It is possible to provide other modifications of the circuitshereinabove shown and described in which direct current train propulsionand alternating current track circuits are used wherein resistors,capacitors, inductors, and transformers are connected to the relay orrelay equipment group to nullify and/ or counteract the effect of thedirect current on the relay.

In the modification shown in FIG. 7, direct current is used throughoutthe track circuit. Here the feed end equipment group 50 is comprised ofa direct current source 51, such as a battery, rectifier, ormotor-generator set, a resistor 52 and a fuse 53. These elements areconnected in series across the track rails at the feed end of the trackcircuit. The relay end equipment group 54 is comprised of a directcurrent source 55, a resistor 56 and a fuse 57, connected in series tothe relay 58 and the track rails at the relay end of the track circuit.The relay 58, in this circuit, is of the biased neutral type. Thevoltage of source 55 is less than that of source 51 and is of oppositepolarity to it. Thus when the track section is unoccupied the resultantvoltage ofthe circuit is in a direction to keep the relay vane in theupward position, and when a train is on the track rails (shunting outsource 51) the circuit voltage is in the opposite direction and holdsthe relay vane in the downward position against the action of any straycurrents or vibration.

Although we have shown .the invention exemplified by several differenttypes of circuits it should be understood that other groupings ofelectrical units not shown or described herein may be used to formcircuits different from those described herein but which circuits willembody the basic principles and ideas herein set forth. Therefore, we donot wish to limit ourselves to the precise circuits herein disclosed,and we therefore reserve the rights to all changes and modications ofthe invention coming within the scope of the invention as dened in anyor all of the appended claims.

Having thus described our invention, what we claim as new and desire tosecure by United States Letters Patent 1S: A track circuit comprised ofa pair of running rails, a feed end source of alternating current, arelay end source of alternating current, a two element alternatingcurrent relay with a center tapped track Winding and a balancingimpedance, said feed end source being secured across the running railsand said relay end source of current, relay and impedance beingconnected in series to a rail, and said feed end source being ofopposite polarity to and greater magnitude than the relay end source ofcurrent, and said impedance being inserted in the relay end of the trackcircuit with its free ends connected to the outside leads of the trackwinding and with its joined end connected to one of the rails, wherebywhen the running rails are unoccupied the resultant current from thesources causes the relay to function in one way, and when the runningrails are occupied by a train the current from the feed end source isshunted away from the relay and the current from the relay end sourceoperates the relay in another way.

References Cited in the file of this patent UNITED STATES PATENTS1,812,164 Mishelevich June 30, 1931 1,812,192 Bone June 30, 19312,666,131 Mishelevich Jan. 12, 1954 FOREIGN PATENTS 941,621 Germany a..Apr. 12, 1956 Y OTHER REFERENCES Union Switch and Signal Bulletin No.37, October 1908.

